Growing
Vegetables under Low Cost Protective Structures
 |
| Protected Cultivation (Photo Source: www.icarda.org) |
Vegetables are generally sensitive to
environmental extremes and thus high temperatures and limited soil moisture are
the major causes of low yields and the condition is going to further intensified
by climate change. These constraints can be alleviated by adopting protective structures
with the intention of growing crops where the extreme conditions are existed. Protected
vegetable production is practiced throughout the world irrespective of altitude
of the place since several hundred years.
Written by Avijit Kumar
Dutta.
INTRODUCTION
Horticultural crops form an integral part of food,
nutrition and economic security. Adoption of horticulture, both by small and
marginal farmers has brought prosperity in various regions of the country as
India is endowed with several agro-climatic conditions. Our country blisses with
a privileged position in the horticulture sector of the world. India is the
second largest producer of vegetables in the world, next to China. India’s
share of the world vegetable market is around 14.0% (Vanitha et al.,
2013). It produces 162186.6 thousand
tonnes of vegetables from an area of 9205.2 thousand hectares (NHB, 2013). According to
statistics released by the Ministry of Agriculture, Government of India, there
has been 13.5% increase in area and 13.4% increase in vegetable output during
the period 1996 to 2010. In spite of all these achievements, per capita
consumption of vegetables in India is very low (180 g/day/capita) against WHO
standards (300 g/day/capita as recommended by FAO). Vegetables are generally
sensitive to environmental extremes and thus high temperatures and limited soil
moisture are the major causes of low yields and the condition is going to further intensified by climate change. These constraints can be alleviated by
adopting protective structures with the intention of growing crops where the
extreme conditions are existed. Protected vegetable production is
practiced
throughout the world irrespective of altitude of the place since several
hundred years. Protected cultivation enables vegetable growers to realize
greater returns per unit of land and offer other benefits, like early harvest,
longer harvest duration, reduced leaching of fertilizers and eco-friendly
management of pests, weeds and diseases (Kumar et al., 2007). Protective
structures also enable growers to produce vegetables successfully during the
off-season, which enhances the availability of fresh produce at times when
vegetables are usually in short supply. Off-season cultivation of cucurbits
under low plastic tunnels is one of the most profitable technologies under
northern plains of India. Walk-in tunnels are also suitable and effective to
raise off-season nursery and off-season vegetable cultivation due to their low
initial cost. Insect proof net houses provide virus free ideal conditions for
productions of different vegetables. Leafy vegetables, tomato, brinjal,
cabbage, cauliflower, broccoli, yard-long bean and bitter gourd can be grown
successfully in net houses (Talekar et al., 2003). These low cost
structures are also suitable for growing pesticide-free green vegetables those
are comparatively safer than the conventionally grown crops. Besides these, the
perpetual demand of vegetables and attenuation of land holdings in India
emphasizes protected cultivation as the best and suitable alternative (Sirohi
and Bahera, 2000).
practiced
throughout the world irrespective of altitude of the place since several
hundred years. Protected cultivation enables vegetable growers to realize
greater returns per unit of land and offer other benefits, like early harvest,
longer harvest duration, reduced leaching of fertilizers and eco-friendly
management of pests, weeds and diseases (Kumar et al., 2007). Protective
structures also enable growers to produce vegetables successfully during the
off-season, which enhances the availability of fresh produce at times when
vegetables are usually in short supply. Off-season cultivation of cucurbits
under low plastic tunnels is one of the most profitable technologies under
northern plains of India. Walk-in tunnels are also suitable and effective to
raise off-season nursery and off-season vegetable cultivation due to their low
initial cost. Insect proof net houses provide virus free ideal conditions for
productions of different vegetables. Leafy vegetables, tomato, brinjal,
cabbage, cauliflower, broccoli, yard-long bean and bitter gourd can be grown
successfully in net houses (Talekar et al., 2003). These low cost
structures are also suitable for growing pesticide-free green vegetables those
are comparatively safer than the conventionally grown crops. Besides these, the
perpetual demand of vegetables and attenuation of land holdings in India
emphasizes protected cultivation as the best and suitable alternative (Sirohi
and Bahera, 2000).
PRESENT STATUS OF PROTECTIVE CULTIVATION IN INDIA
The idea of growing plants in environmentally
controlled areas has existed since Roman eras. The Roman Emperor Tiberius (42
to 37 BC) daily ate cucumber grown through artificial methods (similar to the
greenhouse system). The gardeners planted cucumbers in carts that were wheeled
into the sunlight by day and brought indoors by night to protect them from the
elements. This was an innovative form of the greenhouse. In
the 16th century, European explorers brought back exotic plants
acquired in the course of their travels. Many were tropical plants that could
not survive the cold European climates. The result was the creation of
greenhouses that would progress from the Italian “botanical gardens” to wooden
structures to the more stable cast iron frames and eventually to glasshouses.
Later, with the advent of plastics during the World War-II a new phase in the
greenhouse technology emerged. At present nearly 90 per cent of the new greenhouses
are being constructed by utilizing ultra violet (UV) stabilized polythene
sheets as the glazing material. There are more than 55 countries now in the
world where cultivation of crops is undertaken on a commercial scale under cover
and it is continuously growing at a faster rate globally. China is the largest
users of greenhouses including poly-houses with 2,760,000 ha area coverage (Kacira,
2011). India’s first
exposure to truly hi-tech protected farming of vegetables and other high-value
horticultural produce came through the Indo-Israel project on greenhouse
cultivation, initiated at the New Delhi-based Indian Agricultural Research Institute
(IARI) in 1998, shortly after the establishment of diplomatic ties with that
country.
sheets as the glazing material. There are more than 55 countries now in the
world where cultivation of crops is undertaken on a commercial scale under cover
and it is continuously growing at a faster rate globally. China is the largest
users of greenhouses including poly-houses with 2,760,000 ha area coverage (Kacira,
2011). India’s first
exposure to truly hi-tech protected farming of vegetables and other high-value
horticultural produce came through the Indo-Israel project on greenhouse
cultivation, initiated at the New Delhi-based Indian Agricultural Research Institute
(IARI) in 1998, shortly after the establishment of diplomatic ties with that
country.
However, the Israeli experts left India in 2003 at the end of this
five-year project, IARI continued to maintain the facility, calling it the
Centre for Protected Cultivation Technology (CPCT). It has, in the past 10
years, managed to refine and upscale the system to reduce costs, besides
designing greenhouse structures to suit local conditions. The area under
greenhouse cultivation, reported by the end of 20th century was
about 110 ha in India (Mishra et al., 2010). During last decade this
area must have increased by 10 per cent if not more. The states that have
consistently expanded the area under protected cultivation for the period of
2007-2012 are Andhra Pradesh, Gujarat, Maharashtra, Haryana, Punjab, Tamil Nadu
and West Bengal. Maharashtra and Gujarat had a cumulative area of 5,730.23
hectares and 4,720.72 hectares, respectively under the protected cultivation
till 2012 (Nair and Barche, 2014).
LOW COST PROTECTIVE STRUCTURES FOR GROWING
VEGETABLES
Protected cultivation
practices can be defined as a cropping technique wherein the micro environment
surrounding the plant body is controlled partially/fully as per the need of plant
during their period of growth to maximize the yield and resource saving. Greenhouse
is the most practical method of accomplishing the objectives of protected
cultivation (Nagarajan et al., 2002). Tomato, capsicum and cucumber are
the most extensively grown vegetables under green houses and give higher returns
(Chandra et al., 2000). Growing of cucumber using cost effective plastic
greenhouses provides an alternative for raising crop in the period of scarcity and
ensures to meet year round supply of fresh produce as well with more efficient
resource utilization (Sharma et al., 2009). Protected cultivation
technologies are being utilized all over the world but the level and extent of
their use may be different among different countries. Dixit (2007) studied the
performance of leafy vegetables under protected environment and open field
condition. Greenhouse crops yield several times more than the yields obtained
from outdoor cultivation depending upon the cropping system and the degree of
environmental control. Because of environmental control, any crop can be grown
at any time of the year and even one type of the crops can be raised round the
year if needed. The study also revealed that the greenhouse cultivation showed
superior yield and yield attributing characters as compared to open field
condition. Several low cost protective structures may be utilized for off-season
production of vegetable nurseries as well as for raising crops of high value
vegetables. Few of such low cost protective structures are stated hereunder:
Raising nursery under low cost polyhouse: The low cost poly houses are
made with PVC pipes and tied with sutli. These structures are covered
with 700 gauges (200 μm) UV stabilized polythene sheet. The seedlings are
raised in two types of containers viz. polybags and portrays. Well
decomposed and sieved farmyard manure in combination of FYM: sand: soil in
ratio of 2:1:1 by volume is used as growing media. For cucurbits, the polybags
of 9 cm x 5 cm sizes are filled with the above mixture (FYM, sand and soil)
keeping 2-3 cm vacant from the top. 3-4 fine holes are made at the bottom of
filled bags to drain extra water during irrigation. The filled bags are kept
inside poly house in groups in such a way that one person can easily sow the
seeds and work. A poly house of 10 m x 5 m size could accommodate 8000
polythene bags (9 cm x 5 cm sizes) on ground. After 30-35 days of sowing, when
the seedlings become 10-12 cm long with four true leaves stage, they are kept
outside the polyhouse for 2-3 days for hardening by holding irrigation for two
days. Hardening of vegetable seedlings before transplanting in the main field is
very effective in reducing transplanting shock and also resulted in better crop
stand. In the first week of February when danger of frost is over, the seedling
are transplanted on the northern slope of prepared channels in the field after
removing the polythene bags with the help of blade without distributing the
earth ball. After transplanting, light irrigation is to be given for better
establishment of plants. The vertical space of polyhouse was occupied by
preparation of two stories bamboo benches on which 7000 seedlings of cucurbits
can be grown successfully in portrays. The approximate cost of construction of
polyhouse of 50 m2 [10 m (L) x 5 m (W)] with 7 ft. height is Rs.
15,500/- and such low cost structure has the potentiality to achieve net profit
of about Rs. 9500/- (1st year); Rs.25000/- (2nd year); Rs.24,
000/- (3rd year) [Yadav et al., 2014] considering the life
span of such structure for three consecutive years.
Growing vegetable crops under temporary protected
low height polyhouse: Vegetable crops like French bean, amaranth
and summer squash which are determinate in growth habit and could not be grown
under open field condition during winter season successfully. These vegetables are
grown under low height low cost temporary poly structure and it is highly
suitable for raising these crops during off season. Seeds are sown on raised
bed during 2nd fortnight of November and whole bed is covered with
low height poly structure after sowing and it is made airtight. The seeds
germinated due to conducive environment under protected structures. Once all
the seeds have germinated the polythene sheet is removed daily from both end
during sunny day and again covered in evening to maintain the inside
temperature optimum. All the cultural practices recommended for cultivation of
the crops raised under protected structures are followed. In February when
outside temperature is ideal and chances of occurrence of frost are over, the
polythene sheet is removed and structure is dismantled and kept safely for
future use. The cost of construction of temporary protected low height poly
structure [10 m (L) x 5 m (W) and 3 feet height] is approximately Rs. 9540/-
(Yadav et al., 2014).
Rain shelters: Rain shelter, an
important low cost structure for growing vegetables under tropical climate of
our country, is constructed with low cost materials like Casuarina pole
or any other available material affordable by the farmers. Cladding
material like 200 micron UV stabilized polythene sheet may be utilized.
Vegetables cultivated successfully in rain shelters are amaranthus, salad
cucumber, chilli, cabbage, cauliflower, radish, capsicum, bitter gourd, tomato,
carrot, bhindi, beetroot, brinjal, spinach, cowpea etc. Year round
production of vegetables of good quality with minimal use of insecticides under
the rain shelters is also possible. High value crops like cucumber, capsicum
and off season production of tomato and bhindi resulted in bumper yield of high
quality, with reduced pest and disease incidence under rain shelters. Yield of
the crops may be higher by 2-4 times than in open conditions (Geetha Lekshmi,
2013).
Net houses: Net house and poly
house technology has been recommended for the cultivation of different
vegetables. Net houses are used for raising vegetable crops in high rainfall
regions. Roof of the structure is covered with suitable cladding material.
Sides are made of wire mesh of different gauges. Such structures are useful for
northeastern hilly region. Sweet pepper, an economically potential vegetable is
generally grown at high altitude (> 1000 ft.) but more recently its
cultivation is gaining popularity in Northern Indian plains where its fruit
size and productivity is very poor because of fluctuations in temperature and
attack of insects-pests (fruit borer, aphid, mite and white fly) under open
field conditions. Therefore there is a great scope for protected sweet pepper
cultivation. Likewise, offseason capsicum production under protected cultivation
is also becoming popular in Indian plains (Devi and Thakur, 2013). Crop yields
can be several times higher in net houses than those under open field
conditions, quality of produce is superior and higher input use efficiencies
are achieved through this type of protective cultivation practices. Production
of vegetables under protected conditions involves protection of production
stage of vegetables mainly from adverse environment conditions such as
temperature, hails, scorching sun, heavy rains, snow and frost. The production
of off-season vegetable crops under net house conditions was evaluated by Cheema
et al. (2004) for total yield, earliness and other character and
incidence of insect pests. The cultivation of vegetables in net house can play
a better role in improving quality, advancing maturity as well as increasing
fruiting span and productivity.
Plastic Low Tunnels: Plastic low tunnels are
miniature form of greenhouses to protect the plants from rains, winds, low
temperature, frost and other vagaries of weather. The low tunnels are very simple structures
requiring very limited skills to maintain and easy to constructs and offer
multiple advantages. For construction of low tunnels, plastic film of 100
micron would be sufficient. Row covers or low tunnels are flexible
transparent covering that are installed over the rows or individual beds of
transplanted vegetables to enhance plant growth by warming the air around the
plants in the open field during winter season. They can also warm the soil and
protect the plants from hails, cold wind, injury, and advance the crop by 30 to
40 days than the normal season. This low cost technology is suitable for off
season cultivation of cucurbits like muskmelon, round melon, long melon, bitter
grand, bottle gourd, summer squash etc. and may be quite cost effective
for the growers in northern parts of the country where the night temperature
during winter season goes below 80C for a period of 30-40 days. Walk-in tunnels are comparatively higher than
low tunnels but yield is higher than low tunnels. The tunnel is suitable for
growing tomatoes, cucumbers, sweet pepper and hot pepper. High tunnels, on the
contrary, give maximum yield of crops and make easy soil preparation, picking,
spraying due to its width and height. The high tunnel is also suitable for
growing tomatoes, cucumbers and sweet peppers.
Trenches: This is a very simple,
cheap and common greenhouse structure especially for the cold region of the
country. Defense Research and Development Organization (DRDO) has standardized
trench cultivation method for raising early nursery of vegetables. Seedlings are
raised in polythene covered trenches of appropriate size, generally 15' x 5' x
3' during April and transplanted as soon as cropping season starts. Although
the size of trench depends on the availability of the land but trenches with (9.0
m x 3.0 m x 0.9 m), (10.0 m x 4.0 m x 1.0 m) etc. are considered the
common for growing different vegetables. In this pit type of structure, wooden
poles are used to hold UV stabilized polyethylene film. The polyethylene is
also covered by an additional polyethylene film or woolen or cotton sheet
during night to reduce heat loss in extreme winter. Trenches may also be utilized
for growing vegetables in the areas with higher degrees of scorching sunlight
particularly during summer months. Cabbage, cauliflower, knol-khol,
tomato, capsicum, brinjal, cucumber and other cucurbits can successfully be
grown in trenches.
CONCLUSION
Rapid growth of population coupled with
urbanization and industrialization lead to shrinkage of cultivable lands that
deserve protective cultivation as viable option to meet the food and nutritional
requirements of our over growing population. Protected cultivation of high
value vegetables has shown tremendous potential during the last decade or so.
With the progress of liberalized economy and the advent of newer technologies
in agriculture, protected cultivation opens up avenues in agriculture hitherto
not seen. These technologies are not only creating avenues at higher level but
also to the growers with the smaller landholdings as the higher productivity
levels retain economic relevance to agriculture. Due to inadequacy of advanced
production technology of vegetables, most of the farmers are limited to grow
seasonal vegetables and are dependent on marketing mechanism of demand and
supply so could not get good prices to sustain vegetable business. In
this context, economically viable and technologically feasible low cost
protective structures suitable for the Indian agro-climatic and geographical conditions
for growing different off-season vegetables are desired at the earliest. Cost
effective agro-techniques for growing of several vegetable crops in the
different types of poly houses and lowering energy costs of the greenhouse environment
management are needed to be taken into consideration. Vegetable production
under protective structures reduces yield losses from insect pests, diseases
and heavy rains and results in higher productivity and returns per unit area.
Protective structures enable growers to produce vegetables successfully during
the off-season, which enhances the availability of fresh produce at times when
vegetables are usually in short supply. As prices of vegetables are higher
during the off-season, thereby, growers can enjoy higher returns per unit area
as well.
References
Chandra, P.; Sirohi, P. S.;
Behera, T. K. and Singh, A. K. (2000). Cultivating vegetables in poly-house. Indian
Horticulture, 45: 17-25.
Cheema, D. S.; Kaur, P.
and Kaur, S. (2004). Off-season cultivation of tomato under net house
conditions. VII International Symposium on Protected Cultivation in Mild Winter
Climates: Production, Pest Management and Global Competition. Acta Horticulturae
(ISHS), 659:177-181.
Devi, M. B. and Thakur,
N. (2013). Protected Cultivation as an Emerging Agri-Entrepreneurship in Hilly
Regions of India. Popular Kheti, 1(1): 21-25.
Dixit, A. (2007).
Performance of leafy vegetables under protected environment and open filed
condition. The Asian Journal of Horticulture, 2 (1): 197-200.
Geetha Lekshmi, P. R. (2013).
Rain shelters- A tool to strengthen family farming. LEISA India, 15(4):
27.
Kacira, M. (2011). Greenhouse
Production in US: Status, Challenges, and Opportunities. Presented at CIGR 2011
conference on Sustainable Bioproduction WEF 2011, September 19-23, 2011 at
Tower Hall Funabori, Tokyo, Japan.
Kumar, M.; Kohli, U. K.;
Gupta, S. K. and Vikram, A. (2007). Effect of growing media, irrigation regime,
fertigation and mulching on productivity of tomato in naturally-ventilated poly-houses
in hills. Indian Journal of Agricultural Sciences, 77(5): 302-304.
Mishra, G. P.; Singh, N.;
Kumar, H. and Singh, S. B. (2010). Protected Cultivation for Food and
Nutritional Security at Ladakh. Defence Science Journal, 61(2): 219-225.
Nagarajan, M.; Senthilvel,
S. and Planysamy, D. (2002). Material substitution in Greenhouse construction. Kisan
World, 11:57-58.
Nair, R. and Barche, S. (2014).
Protected Cultivation of Vegetables – Present Status and Future Prospects in
India. Indian Journal of Applied Research, 4 (6): 245-247.
NHB
(2013). National Horticulture Board, Ministry of Agriculture, Government of
India, Indian Horticulture Database- 2013. p. 10.
Sharma, M.; Negi, S. and
Kumari, S. (2009). Effect of different growing media and fertigation levels on
production of cucumber (Cucumis sativus L.) under protected conditions
in the hills. Indian Journal of Agricultural Sciences, 79 (10):
853-856.
Sirohi, P.S. and Bahera,
T. K. (2000). Protected cultivation and seed production in vegetables. Indian
Horticulture, 45: 23-25.
Talekar, N.S.; Su, F.C.
and Lin, M.Y. (2003). How to produce safer leafy vegetables in net houses and
net tunnels. Asian Vegetable Research
and Development Center, Shanhua, Tainan, Taiwan. pp.18.
Vanitha, S.M.; Chaurasia,
S.N.S.; Singh, P.M. and Prakash S. Naik. (2013). Vegetable Statistics. Technical
Bulletin No. 51, IIVR, Varanasi, pp. 250.
Yadav, R. K.; Kalia, P.;
Choudhary, H.; Husain, Z. and Dev, B. (2014). Low-Cost Polyhouse Technologies
for Higher Income and Nutritional Security. International Journal of
Agriculture and Food Science Technology, 5(3): 191-196.
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Avijit Kumar Dutta. Assistant Professor (Horticulture), RKMVU, F/C for Ranchi
E mail: avijitkumardutta@gmail.com
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